The Study of Oral Health in Greece will be carried out in Athens, Greece in collaboration with the Dr. Athanasios I. Zavras, Project Director of the Molecular Epidemiology of Oral Cancer Study and post doctoral fellow at the Harvard University, School of Dental Medicine, Department of Oral Health Policy and Epidemiology. Dr. Zavras, an oral cancer epidemiologist, has been conducting an epidemiologic (case-control) study of oral cancer in selected hospitals in Athens, Greece. The MEDIB is collaborating with Dr. Zavras on the molecular and statistical analyses to be performed for this study. Risk factors, family histories of cancer and biological samples (oral rinses and brushings, tumor biopsy or surgical specimens (if available) and blood spots on filter paper) will be delivered to the MEDIB laboratory for each patient and control. The MEDIB laboratory will apply semi-automated technologies for genetic analysis to evaluate genes potentially responsible for oral cancer. The roles of human papilloma virus, including interaction with and variation at the HLA and other key chromosomal regions, will be a major focus of the MEDIB research. In addition, molecular analyses will be conducted to assess mutations in oncogenes and tumor suppressor genes in tumor tissues, and polymorphic variation in metabolic detoxification pathways among cases, controls and the baseline samples. The study population will consist of approximately 100 cases, 100 controls plus a baseline sample =>100.